It's not that we "can't."
We were told not to by the Aliens based on the dark side.
Yeah. I’m still hearing we can’t go back to the Moon.
I guess it’s because engineers are no longer taught to use slide rules...
We can’t go back to the moon at current because of all the industry and knowledge that was destroyed and no longer exists. You can’t just wave your wand and have parts appear from nowhere; just like you can’t just think happy thoughts and build a brand new 1969 Cadillac Fleetwood Sixty Special - the suppliers don’t exist any more, the tooling doesn’t exist, the line to build it doesn’t exist any more.
The technology base has to be rebuilt/redeveloped in order to build something like a 69 Cadillac today. Same thing with the Saturn V. And since you have to go to such expense and trouble, you might as well just start over and build something new that is advised by the developments and advances between the old design and now. Which, actually, is what’s going on now.
But yes, at this time, we do not have the ability to build a craft to take men to the moon. New moon craft are *being designed* and developed, but nothing we can put into production today.
It's not that we "can't."
We were told not to by the Aliens based on the dark side.